Please review codes (formatted per MrShorty)

Hi all, hope you can weigh in on my '95 XLTs codes Ive recently pulled. For history, see the following thread http://www.explorerforum.com/forums/showthread.php?t=158616

Short version:
Recent history includes cylinder head leaking coolant, transmission failed and replaced one year ago (Phoenix reman), new thermostat, rad. cap, throttle body cleaning.

During a long camping trip last week while I was worrying about the cylinder head leak, I started getting intermittant CEL light, and flashing O/D light in the mountains. I disconnected battery after arriving and after leaving days later the CEL and O/D flashing resumed. O/D never stopped working and functions normally. CEL light never stays on for long. Transmission has entered oft-mentioned "safe" mode with resultant Ka-chunk downshift between 2nd and 1st while coming to a stop.

Here are the codes Ive pulled (big thanks to MrShorty for the directions).
All codes diciphered using www.troublecodes.net

KOEO
335 - "Pressure feedback EGR sensor voltage higher or lower than expected"
Not sure this would cause a flashing O/D

CM
122 - "TPS circuit below min. voltage"
647 - "Improper gear ratio in 3rd gear" The big one, obviously.

KOER
326 - "Pressure feedback EGR circuit voltage low"
632 - "Torque converter solenoid circuit did not change states during KOER"
Note: according to troublecodes.net, code 632 is a CM code, but it only occurred during KOER.

I think its clear that ill be gaining experience with Phoenix's warranty program shortly. I am now extremely pleased with myself for getting the extended "Platinum" warranty.

Does anyone have any insight to add? Do the EGR and TPS codes appear to be complimentary or stand alone in relation to the trans problem?

By the way, I also did the SEFI test described at the end of the instructions. The test appeared to go well, but the CEL light blinked 9 times after completion. Does anyone know what that indicates?

This being Saturday as I write this, Im going to go clear all codes and drive a while and retest. Ill post those results as well.

Thanks very much for your consideration

Here is an update. I erased all codes per instructions and disconnected battery.

I drove it on surface streets for 10 miles like a timid granddad. No lights, no problems.

After 10 miles I got on the freeway and babied it up to 70 mph. No lights, no problems.
Then I started to test it harder, downshifting, accelerating harder. No lights, no problems.

Back on the surface street, I was now outright abusing it. Jackrabbit starts, WOT at 40mph. I did feel some harder downshifts coming to fast stops. Still though, no lights, no problems.

At home again I checked and found codes despite the fact that the CEL never lit up

KOEO - 335 - Same as before - EGR sensor voltage

CM - 111 - No codes! Pass.

KOER - 326 - Same as before -EGR circuit voltage
632 - Same as before - Torque converter solenoid...

So I dropped the TPS code and the 3rd gear code.

Heres a question. Could this have been caused by me not turning the O/D off when we entered the hills? The truck was loaded to the gills and I simply forgot.

I guess we'll see over the next few days.

A few thoughts:

A KOEO 335 indicates a hard fault in the DPFE sensor circuit. As there seem to be fairly frequent complaints about the DPFE, I think I would explore this a little bit. Shouldn't be too hard. Basically it seems to boil down to checking the wiring between the DPFE and the computer. If that checks out, then replace the DPFE.

I think the KOER 632 is usually a result of not pressing the O/D cancel switch during the KOER test. I guess I forgot to mention this step in my "note" thread, because I've never pulled codes on a '95 with an O/D cancel switch. I think this is supposed to be at the same time as pressing the brake just after engine id.

As for the CM codes: not much you can do but wait and see if they come back.

Thanks for the reply.

After reading all the posts here about failed DPFEs, its clear this is a long standing fault that probably has nothing to do with the flashing O/D. For now Ill just act on that as if it was separate.

I'll re-do the KOER test and this time will cycle the O/D switch as you noted, then report back.

I still dont know what would cause the O/D light to flash and the trans to enter the harder shifting mode. Perhaps it had something to do with the load on the vehicle at the time.

Anyway this has all been good education so far.

Small update for future readers.

I changed the DPFE, $50 at Autozone (known as the EGR Sensor). All EGR codes disappeared from KOEO, CM, and KOER.

Im code free. Happy days...